Increased repeat syphilis among HIV-infected patients

Among human immunodeficiency virus (HIV)–infected individuals, syphilis is an important sexually transmitted infection (STI), and repeat infections are common. Identifying risk factors for delineating the trends in repeat syphilis are essential for STI and HIV prevention. This study is to investigate the dynamic of the syphilis epidemic among HIV-infected patients and to identify the risk factors associated with repeat syphilis. A population-based cohort design was used to analyze claim data between January 2000 and December 2010 using the Taiwan National Health Insurance Research Database. The Poisson regression test was used to identify risk factors for repeat syphilis. Of 13,239 HIV-infected patients, annual syphilis screen tests have been performed in 4,907 (37.1%) of these patients. Syphilis has been diagnosed in 956 (19.5%) patients, and 524 (10.7%) had repeat syphilis. The annual trend in repeat syphilis showed a significant increase in the study period (β = 0.23, P